Leases - Supplemental Balance Sheet Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Leases [Abstract]
Operating cash flows from operating leases	$ 23,644
Operating lease assets, net of accumulated depreciation	128,529
Current operating lease liabilities	(61,198)
Operating lease liability	(69,195)
Total lease obligations	(130,393)
Finance leases
Property and equipment, gross	8,418
Accumulated depreciation	(5,063)
Property and equipment, net	3,355
Other current liabilities	(2,101)
Financing lease liability	(1,320)
Total lease obligations	$ (3,421)
Weighted average remaining lease term (in years), operating leases	3 years
Weighted average remaining lease term (in years), finance leases	1 year 9 months 18 days
Weighted average discount rate, operating leases	4.70%
Weighted average discount rate, finance leases	5.60%
Investing cash flows from operating leases	$ 71,487
Operating cash flows from finance leases	242
Financing cash flows from finance leases	2,746	$ 0	$ 0
Right-of-use assets obtained in exchange for lease obligations, operating leases	109,681
Right-of-use assets obtained in exchange for lease obligations, finance leases	$ 2,618